Wind turbine blades can suffer significantly from erosion due to exposure to the elements, such as rain, hail, sand, or other particulates. Turbine compressor blades used in devices such as gas turbines, aircraft engines, microturbines, steam turbines, and the like, suffer from erosion due to water droplets contacting the blades during operation. For instance, erosion pitting can be caused by water condensation on the blades or by water washing to remove deposits during turbine operation.
Turbine blades can also suffer from corrosion as a result of the harsh operating environment in which the turbine blades are used. Corrosion pitting works in synergy with existing erosion pits to generate an overall faster pit growth rate. Corrosion and erosion pitting can cause catastrophic failure of the turbines if left undetected or unmitigated.
It is difficult to monitor erosion and corrosion of turbine blades. For instance, wind turbine blades are typically located in remote locations and special equipment is need to access the turbine blades for inspection. Expensive machine downtime is typically required to inspect turbine compressor blades, such as blades used in gas or steam turbines, to detect and monitor erosion and corrosion pit depths.
Thus, a need exists for a sensor that can separately monitor both erosion and corrosion of a turbine blade. A sensor that can provide detection of erosion and corrosion pit depths during turbine operation, without requiring machine downtime, would be particularly useful.